The proposed research seeks to contribute to an emerging literature that assesses the philosophical implications of the ecological concepts, metaphors, and analogies that are beginning both to frame our understanding of the human microbiome and to challenge entrenched mechanistic concepts of the human body and the human being -- entrenched concepts that not only include the "blueprint" analogies of the Human Genome Project but stretch back at least to the discovery of the circulation of the blood. The proposed research will use philosophical analysis to explore and assess in the context of the Human Microbiome Project the application of ecological metaphors - such as "community," "superorganism," "homeostasis" "ecosystem," "dynamics," "complexity," etc. - to public and scientific understanding of such concepts as the "human body," the "human being" and the "human individual." The project acknowledges well-known problems in the ecological sciences that beset and may, indeed, defeat the application of concepts that attempt to unite organisms into natural systems and communities. The research proposed here will explore whether these kinds of problems also complicate the application of ecological concepts in the study of the human microbiome and metagenome. The proposed research will examine how normative concepts, such as "structure," "function," "interdependence," "community," and even "system" have moved back and forth between the medical and ecological sciences. It will discuss moral and conceptual implications of ecological images of the human individual - for example, the picture of the individual as a composite of microbial and human cells, the representation of the human genome as a kind of landscape, and the idealization of the microbiome as a kind of mixmaster of human and microbial traits. The proposed project will produce published papers and conference presentations that will help scientists concerned with the microbiome and metagenome to understand the ecological framework in which they may set their research. PUBLIC HEALTH RELEVANCE: Public health research now presses on the frontiers of the human microbiome and metagenome but lacks a conceptual framework to integrate these microbial and genetic landscapes into recognizable images of the human being, the person, and the individual. By assessing through philosophical analysis emerging ecological concepts, metaphors, and an analogies in terms of which scientists frame their research, the proposed project will help clarify the goals of the Human Microbiome Project (HMP) in its relation to conceptions the patient and patient health the HMP seeks to serve.